1. Field of the Invention
The present invention relates to an image data processing device and an image data processing method. More specifically, the present invention relates to an updating process of an image data index when image data are deleted.
2. Description of Related Art
In recent years, digital image data processing devices including a DVD (Digital Versatile Disk) recorder and an HDD (Hard Disk Drive) recorder have become widely available as devices for recording and reproducing image data (contents) handled in image processing devices such as a television set. As one of functions of the image data processing devices, there is a playlist (image data index) function.
The playlist function is a function utilizing a random access function that is equipped to recording media including a DVD and an HD. The random access function means a function for performing various image processes by using positional information (address information) in the image data obtained from recording process. The recording medium having the random access function facilitates editing or the like of recorded contents without a special editing device.
For example, when reproduction of contents is halted, address information of the halted position can be set easily as a restart position for the next reproduction by using the random access function. Thus, a user can play the contents from the position halted last time easily without a fast forward operation or the like.
Furthermore, for example, extracting a part of the image or combining extracted images can be performed by designating a plurality of address information of a plurality of contents. In other words, a part or a whole of a plurality of contents can be played continuously in any order. A set of the address information for playing continuously as described above is usually called a playlist. A function for creating such a playlist or for performing continuous playing using a playlist is the playlist function.
As a conventional technique about the above-mentioned playlist function, JP-A-2004-208172 discloses an image data processing device, which can reset easily a boundary position of partial areas of image data registered on the playlist (a part or a whole of image data extracted based on address information).
In general, when a new playlist is created from a partial area registered on the playlist, a leading portion or a trailing portion of the image or the sound included in a range of the partial area may be cut, or an undesired scene may be added to the leading portion or the trailing portion in the partial area. In this case, the user of the image data processing device in many cases has no choice but to adjust the partial area when setting the partial area of original data (image data to be an original of the partial area to which the playlist refers). On the other hand, an image data processing device disclosed in JP-A-2004-208172 can edit the partial area on an edit display (playlist creating display) afterward, for performing reset such that a boundary area between cells is shifted or that an entry point (EP) in a cell is shifted.
If a user can reset a start point and an end point of a partial area easily in this way, it is possible to create a high quality edited image particularly in the edit process (playlist creating process).
However, in the playlist function equipped to the conventional image data processing device disclosed in JP-A-2004-208172, it is necessary to delete the playlist that refers to the original data to be deleted (the playlist created by using the partial area of the data to be deleted) or to update contents of the same when the original data is deleted. In this case, in order to detect all the playlists that refer to the data to be deleted, it is necessary to search a MAP information (information indicating which playlist refers to which original data) of all the playlists.
A concrete example of the above-mentioned process will be described with reference to FIG. 6. FIG. 6 is a block diagram showing a relationship among original data, original data management data, original data titles and a playlist concerning the playlist function. As shown in FIG. 6, the original data (original data A 61 and original data B 62), the original data management data (original data A management data 51 and original data B management data 52) and the original data titles (an original data A title 41 and an original data B title 42) have a one-to-one relationship, respectively. In the example shown in FIG. 6, there are three playlists (a playlist A 31, a playlist B 32 and a playlist C 33) that refer to the original data management data. Note that a dot and dash line in FIG. 6 indicates a boundary between the management data and real image data. The management data are located above the dot and dash line while the real image data are located below the same.
As an example, a process when a user creates the playlist A 31 will be described. The user selects the original data title of the contents to be registered in the playlist (the original data A title 41 and the original data B title 42 in this example) from a plurality of original data titles. Then, the user performs designation of a range to be extracted (extraction of a partial area) from the original data management data corresponding to the selected original data title (the original data A management data 51 and the original data B management data 52 in this example) (see arrows α1 and α2 in FIG. 6).
The user performs the above-mentioned process once or a plurality of times so that the partial area is extracted. The extracted partial area is stored in a hard disk or the like together with its address information. Then, the user designates an order of reproducing the plurality of extracted partial areas. Information of the reproduction order generated by this designation becomes the playlist A 31.
As another example, a process when a user deletes original data B 62 will be described. When the original data B 62 are deleted, the original data B title 42 and the original data B management data 52 that have a one-to-one relationship are also deleted at the same time. However, since the playlist A 31 and the playlist C 33 refer the original data B management data 52 (see arrows α2 and α4 in FIG. 6), these two playlist must be deleted, too.
The above-mentioned deleting process is performed in the following procedure.
(1) Check that the original data B title 42 and the original data B management data 52 are related to each other.
(2) Confirm contents of all the playlists (the playlist A 31 through the playlist C 33) for checking which playlist is using the original data B management data 52.
(3) Identify the playlists (the playlist A 31 and the playlist C 33) that are using the original data B management data 52 based on a result of the confirmation and delete the playlists.
(4) Delete the original data B title 42, the original data B management data 52, and the original data B 62.
It may take long time for the process of confirming the contents of all the playlists in the step (2) of the above-mentioned deleting process. It is because many playlists of a hundred or more can be created by a DVD recorder or the like that is available on the market at present. In addition, there is a problem that the above-mentioned process itself is complicated.
Although the playlist is created based on the original data in the above-mentioned example, it is also possible to create the playlist based on image data registered in the playlist (a partial area of the original data). Alternatively, it is also possible to create the playlist by using both the original data and the image data registered in the playlist. In these cases, the above-mentioned conventional deleting process has poor processing efficiency, and the number of processing steps increases rapidly. In addition, the processing time necessary for the deleting process of the original data increases in proportion to the number of the playlists. The user may hardly endure the long waiting time until the deleting process is completed.